The present invention relates generally to descalers for descaling the scale on wire which occurs as an undesirable byproduct in the manufacture of hot finished wire or xe2x80x9cgreen rodxe2x80x9d, and more particularly to the initial wire set up of such descalers at a location upstream of a wire drawing machine or other wire consumption machine.
Hot finished wire (also known as xe2x80x9cgreen rodxe2x80x9d) is a desirable material used in many commercial applications. Although hot finished wire has certain desirable characteristics in comparison to other types of wire, the commercial manufacturing process for producing hot finished wire creates scale as an undesirable byproduct on the exterior surface of the wire (also known as xe2x80x9cmill scalexe2x80x9d). It is usually desirable to remove the scale on the wire for a number of reasons including aesthetics.
Descalers are frequently used at an upstream location of wire consumption operations (e.g. wire cutting machines) to remove the scale on the hot finished wire prior to use. Often times, these descalers are located upstream of a wire drawing machine. The wire drawing machine includes a capstan and drawbox for reducing the diameter of the wire. Wire drawing machines are generally disclosed in U.S. Pat. No. 4,917,285 to Shosie; U.S. Pat. No. 5,097,688 to Taylor et al.; U.S. Pat. No. 6,000,656 to Taylor et al.; and U.S. Pat. No. 6,109,082 to Taylor, et al; the entire disclosures of which are hereby incorporated by reference. Descalers often have a mounting flange that mounts directly along the upstream side of such wire drawing machines.
To descale the wire, wire descalers commonly have a pair of sheaves or rollers that are arranged along generally perpendicular axes of rotation. As wire is pulled through the descaler, one roller alternately stretches and contracts the opposing top and bottom surfaces of the wire while the other roller alternately stretches and contracts the opposing lateral side surfaces of the wire. The perpendicular arrangement of the rollers ensures that the outer surface of the wire is effectively stretched, contracted or bent in substantially all directions. Because scale is brittle, the bending of the wire in two different directions causes the scale to fall off the wire and thereby leaves a more desirable exterior finish on the wire. Each roller also typically includes a carbide hub insert at the inner radial periphery of the roller for wear resistance and to engage the wire to assist in scale removal.
During wire drawing operations when an active wire coil is being consumed, the wire descaler works automatically to descale the wire as it is pulled through the descaler. However, once the active wire coil is consumed, the problem arises that the leading end of a new wire coil must be fed through the complex looped path created by the perpendicularly oriented and horizontally spaced rollers of the wire descaler. In the past, set up of wire descalers has been a laborious task requiring extensive manual manipulation of the wire to wind the wire through the rollers of the descalers.
Two commercially available descalers include the RMG MD-10 Descaler Attachment and the RMG MD-14 Descaler Attachment, both manufactured by Rockford Manufacturing Group, Inc., the assignee of the present invention. Both of these descalers have been successful in descaling wire utilizing perpendicularly oriented sheaves or rollers.
In the MD-10 Descaler, the rollers are arranged at fixed positions in perpendicular orientation to each other. Set up of this descaler is accomplished by manually pulling wire through the descaler inlet, manually looping wire around the forward roller, manually bending the wire rearwardly toward the rear roller, and then underneath and around the rear roller and back forward through the descaler outlet. Since all of the bends and loops in the wire are performed manually, it will be readily appreciated by those skilled in the art that this is a fairly laborious task. Even if a worker uses sufficiently long strands of wire to provide additional leverage for wire easier bending, set up of this descaler is still a time consuming task and requires a significant amount of manual effort and skill.
The RMG MD-14 Descaler may be used with heavier wire gauges as compared with the MD-10 Descaler. In the MD-14 Descaler, one of the rollers is movable while the other roller is secured in a fixed position. In the MD-14 Descaler, the rollers are initially spaced horizontally with parallel vertical axes of rotation. To set up this descaler, wire is first pulled through the inlet and the outlet of the descaler and is threaded between the two rollers. A pry bar is often used to align and position the wire among and between the two rollers. The leading end of the wire is then typically pulled through a drawbox and secured to a gripper chain to prevent the wire from back feeding through the outlet during initial set up. After the wire is properly positioned between the rollers, a worker uses a pry bar to manually rotate the movable roller and its support assembly horizontally about and relative to the fixed position roller such that the movable roller is rotated in a semi-circle from the outlet end around the fixed position roller to the inlet end of the descaler. The pry bar is inserted into two different holes to accomplish this semi-circle of rotation. Once the movable roller reaches the inlet end of the descaler, its support assembly locks into position. Then, a worker manually raises and pivots the movable roller upward with the pry bar until the rotational axis of the movable roller is perpendicular to the axis of the fixed position roller. Finally, the wire running through the inlet end must then be manually repositioned to allow for insertion of the vertical guide rollers that typically are provided at the inlet end. Although the set up of the MD-14 reduces the manual handling of the wire, it still requires several different steps of manual effort to set up the descaler. As such, set up of this descaler is still a time consuming task and requires a significant amount of manual effort and skill.
The set up of the MD-14 and the MD-10 descalers are described in further detail in brochures entitled the xe2x80x9cRMG MD-10 Descaler Attachmentxe2x80x9d and the xe2x80x9cRMG MD-10 Descaler Attachmentxe2x80x9d, both dated May, 2000, and available from Rockford Manufacturing Group, Inc. Further detail can be had to those references for further details on the wire set up those machines.
In view of the foregoing, it is a general objective of the present invention to provide a descaler for descaling scale on wire that is easier to set up.
It is another objective of the present invention to provide a descaler having a setup that may be substantially automated.
In accordance with these and other objectives, the present invention is directed toward a wire descaler in which rotation of one or more of the rollers about an offset axis automatically translates the rollers from a set up position in which the rollers are aligned along substantially parallel axes of rotation to a working position in which the rollers are aligned along substantially perpendicular axes of rotation.
According to one aspect of the present invention, a descaler comprises two rollers that are mounted to a rotatable support plate. The support plate and the rollers rotate in unison relative to a housing through rotational input provided along a drive shaft. The drive shaft is journalled in a bearing support housing which is mounted to the housing. At least one of the rollers pivots relative to the support plate. The rollers are movable between a set up position in which axes of the rollers are substantially parallel to provide for feeding of wire through the rollers and a working position in which the axes of the rollers are substantially perpendicular to effect wire descaling during operation when wire is pulled through the descaler. Rotation of the roller support plate from the initial set up position automatically pivots the rollers into the working position. Translation of the rollers from the set up position to the working position may be accomplished using the tension of the wire that is created as the roller support plate is being rotated, a cam mechanism, or a combination thereof.